leetcode 78. 子集

78. 子集

class Solution {
public:
    vector<vector<int> > ans;
    vector<int> V;
    void dfs(vector<int>& nums, int ind) {
        if(ind >= nums.size()) {
            ans.push_back(V);
            return ;
        }
        dfs(nums, ind+1);
        V.push_back(nums[ind]);
        dfs(nums, ind+1);
        V.pop_back();
    }
    vector<vector<int>> subsets(vector<int>& nums) {
        dfs(nums, 0);
        return ans;
    }
};